It was a self-made sci-fi horror scenario, a deep space science surveying vessel investigating a star outputting radiation that drives people mad then physically mutates them through vitrification. Basically, a very thinly veiled Event Horizon + Sunshine mashup type scenario with glass monsters. But in the process I cribbed heavily from the premade sheets, and kudos to you guys, because the universality of the mechanics made cooking up my own Dangers super quick and easy.
I typically do days of prep for anything I run, but I spent like... two hours, tops before running it and basically went with what the players were doing to shape a vague act structure with climaxes of rising seriousness.
I have to give additional praise to the finale mechanics; I've never had a player choose to invoke death via ultimate sacrifice before, the player was smiling as his professor of physics went careening out into the void, taking the final boss horror with him in the process!
So awesome to hear all of this! Event Horizon + Sunshine is a fantastic mashup. Love both of those movies.
I'm so glad the mechanics made things quick and easy. A major goal of the game is just to make it easy to get to the table from all directions--PCs, GM, etc.
My PCs are digging the sacrifice mechanic too! We've had some great sacrifices--not just the story beat, but a clutch way of overcoming a particularly difficult Danger.
If/when you run again, let me know how it goes!